532 research outputs found

    ERP evidence of cognitive strategy change in motivational conditions with varying level of difficulty

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    Recent research suggests that motivation improves cognitive functions but the particular mechanisms and precise behavioural conditions involved in such improvement still remain unknown. Particularly, it is unclear when in time and in which conditions these mechanisms are engaged. In the present study, we aimed to look at the neural markers of cognitive control strategies in different motivational conditions (motivation vs neutral) with different levels of difficulty (high vs low). Twenty-five adults completed a newly designed task in the four conditions above. Three ERP components were analysed: the CNV, LRP and P3b. We found that a motivational situation triggers the use of a proactive strategy when low cognitive control is required. A reactive strategy was used in a non-motivational situation and for difficult trials. Our study is also the first to provide evidence that the difference between proactive and reactive strategies occurs after the first stimulus (cue) is processe

    The experiential blink: Mapping the cost of working memory encoding onto conscious perception in the attentional blink.

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    The attentional blink (AB) represents a cognitive deficit in reporting the second of two targets (T2), when that second target appears 200-600 msec after the first (T1). However, it is unclear how this paradigm impacts the subjective visibility (that is, the conscious perception) of T2, and whether the temporal profile of T2 report accuracy matches the temporal profile of subjective visibility. In order to compare report accuracy and subjective visibility, we asked participants to identify T1 and T2, and to rate the subjective visibility of T2 across two experiments. Event-related potentials were also measured. The results revealed different profiles for the report of T2 versus the subjective visibility of T2, particularly when T1 and T2 appeared within 200 msec of one another. Specifically, T2 report accuracy was high but T2 visibility was low when the two targets appeared in close temporal succession, suggesting what we call the Experiential Blink is different from the classic AB. Electrophysiologically, at lag-1, the P3 component was modulated more by subjective visibility than by report accuracy. Collectively, the data indicate that the deficit in accurately reporting T2 is not the same as the deficit in subjectively experiencing T2. This suggests that traditional understandings of the AB may require adjustment and that, consistent with other findings, working memory (WM) encoding and conscious perception may not be synonymous

    ALMA Observations of the Young Substellar Binary System 2M1207

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    We present ALMA observations of the 2M1207 system, a young binary made of a brown dwarf with a planetary-mass companion at a projected separation of about 40 au. We detect emission from dust continuum at 0.89 mm and from the J=32J = 3 - 2 rotational transition of CO from a very compact disk around the young brown dwarf. The small radius found for this brown dwarf disk may be due to truncation from the tidal interaction with the planetary-mass companion. Under the assumption of optically thin dust emission, we estimated a dust mass of 0.1 MM_{\oplus} for the 2M1207A disk, and a 3σ\sigma upper limit of 1 MMoon\sim 1~M_{\rm{Moon}} for dust surrounding 2M1207b, which is the tightest upper limit obtained so far for the mass of dust particles surrounding a young planetary-mass companion. We discuss the impact of this and other non-detections of young planetary-mass companions for models of planet formation, which predict the presence of circum-planetary material surrounding these objects.Comment: 10 pages, 6 figures, accepted for publication in A

    Occupational Therapy’s Role in Addressing College Campus Well-Being

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    The purpose of this study is to (1) explore occupational therapy’s role in mental health and (2) investigate the effects of Cranial Electrotherapy Stimulation and mindfulness in reducing symptoms of depression, stress or insomnia among college students. This study utilized a pre/posttest design with participants randomized into 2 groups: CES alone (Group A) and mindfulness meditation and CES (Group B). A purposeful sample of college students were recruited, all with a previous diagnosis or self-report of stress/anxiety. This study measured sleep, anxiety, trait mindfulness, and daily function using the Hamilton Anxiety Rating Scale, Freiburg Mindfulness Inventory, Functional Status Questionnaire, and Pittsburgh Sleep Quality Index. Measurements were taken at baseline, weeks 5, 8, and 12. Following intake, students began the 5-week treatment protocol. In week 1, participants completed CES or CES/meditations for 7 days. In weeks 2-5, participants completed 4-5 times/week, 20-40mins each, depending on tolerated dosage. Repeated-measures ANOVA revealed a significant effect of time over 8 weeks for HAM-A [F(1,22) = 19.42, p \u3c 0.05], FMI [F(2,21) = 10.41, p \u3c 0.05], PSQI [F(2,22) = 19.01, p \u3c 0.05], and FSQ Social Role Function [F(2,21) = 5.00, p \u3c 0.05]. There were no significant differences between groups for all four assessments, nor a significant effect of time for the Physical/Psychological FSQ categories. Results reveal that time is the biggest factor in reducing anxiety, and increasing mindfulness, sleep, and daily function, despite differences in groups. This demonstrates that CES and mindfulness might be effective treatment methods for mental health in OT

    Single neuron transient activity detection by means of tomography

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    From Twentieth Annual Computational Neuroscience Meeting: CNS*2011 Stockholm, Sweden. 23-28 July 2011(CA) and (ES) are supported by BFU2009-08473. (CA) and (PP) are partially supported by AYA2009-14212-05. (PP) is partially supported by TIN2010-21575-C02-01

    Modelling Primordial Gas in Numerical Cosmology

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    We have reviewed the chemistry and cooling behaviour of low-density (n<10^4 cm^-3) primordial gas and devised a cooling model wich involves 19 collisional and 9 radiative processes and is applicable for temperatures in the range (1 K < T < 10^8 K). We derived new fits of rate coefficients for the photo-attachment of neutral hydrogen, the formation of molecular hydrogen via H-, charge exchange between H2 and H+, electron detachment of H- by neutral hydrogen, dissociative recombination of H2 with slow electrons, photodissociation of H2+, and photodissociation of H2. Further it was found that the molecular hydrogen produced through the gas-phase processes, H2+ + H -> H2 + H+, and H- + H -> H2 + e-, is likely to be converted into its para configuration on a faster time scale than the formation time scale. We have tested the model extensively and shown it to agree well with former studies. We further studied the chemical kinetics in great detail and devised a minimal model which is substantially simpler than the full reaction network but predicts correct abundances. This minimal model shows convincingly that 12 collisional processes are sufficient to model the H, He, H+, H-, He+, He++, and H2 abundances in low density primordial gas for applications with no radiation fields.Comment: 26 pages of text, 4 tables, and 6 eps figures. The paper is also available at http://zeus.ncsa.uiuc.edu:8080/~abel/PGas/bib.html Submitted to New Astronomy. Note that some of the hyperlinks given in the paper are still under constructio

    The certification of the activity concentration of the radionuclides 137Cs, 90Sr and 40K in wild berries: IRMM-426

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    This report describes the production of CRM IRMM-426, a dried bilberry material certified for the radionuclide activity concentrations of 137Cs, 90Sr and 40K. The material was produced following ISO Guide 34:2009. Bilberry samples were collected in a woodland region of so-called “strontium hot spots” close to the Chernobyl reactor site. The samples were air-dried at the sampling site before transport to IRMM, where the raw material was oven-dried, cryo-milled, sieved, homogenised and bottled. The bottled material was sterilised by gamma-irradiation. Between-unit homogeneity was quantified and stability during dispatch and storage were assessed in accordance with ISO Guide 35:2006. The material was characterised by an intercomparison among laboratories of demonstrated competence and adhering to ISO/IEC 17025. Technically invalid results were removed but no outlier was eliminated on statistical grounds only. Uncertainties of the certified values were calculated in compliance with the Guide to the Expression of Uncertainty in Measurement (GUM) and include uncertainties related to possible inhomogeneity and instability and to characterisation. The material is intended for the assessment of method performance and quality control. As any reference material, it can also be used for control charts or validation studies. The CRM is available in amber glass jars containing about 100 g of dried bilberry powder. The minimum amount of sample to be used for analysis is 50 g for 90Sr and 18 g for 137Cs and 40K.JRC.D.2-Standards for Innovation and sustainable Developmen

    Dyscalculia from a developmental and differential perspective

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    Developmental dyscalculia (DD) and its treatment are receiving increasing research attention. A PsychInfo search for peer-reviewed articles with dyscalculia as a title word reveals 31 papers published from 1991–2001, versus 74 papers published from 2002–2012. Still, these small counts reflect the paucity of research on DD compared to dyslexia, despite the prevalence of mathematical difficulties. In the UK, 22% of adults have mathematical difficulties sufficient to impose severe practical and occupational restrictions (Bynner and Parsons, 1997; National Center for Education Statistics, 2011). It is unlikely that all of these individuals with mathematical difficulties have DD, but criteria for defining and diagnosing dyscalculia remain ambiguous (Mazzocco and Myers, 2003). What is treated as DD in one study may be conceptualized as another form of mathematical impairment in another study. Furthermore, DD is frequently—but, we believe, mistakenly- considered a largely homogeneous disorder. Here we advocate a differential and developmental perspective on DD focused on identifying behavioral, cognitive, and neural sources of individual differences that contribute to our understanding of what DD is and what it is not

    Cost-effectiveness of oral alitretinoin in patients with severe chronic hand eczema - a long-term analysis from a Swiss perspective

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    BACKGROUND: The impact on patients suffering from chronic hand eczema (CHE) is enormous, as no licensed systemic treatment option with proven efficacy for CHE is available. Alitretinoin is a novel agent which showed high clinical efficacy in patients with severe, refractory CHE. We assessed the cost-effectiveness of alitretinoin for CHE patient treatment from a Swiss third party payer perspective. A further objective of this study was to determine the burden of disease in Switzerland. METHODS: A long-term Markov cohort simulation model was used to estimate direct medical costs (euro) and clinical effectiveness (quality adjusted life years, QALYs) of treating severe CHE patients with alitretinoin. Comparison was against the standard treatment of supportive care (optimised emollient therapy). Information on response rates were derived from a randomized controlled clinical trial. Costs were considered from the perspective of the Swiss health system. Swiss epidemiological data was derived from official Swiss Statistic institutions. RESULTS: Annual costs of alitretinoin treatment accounted for 2'212 euro. After a time horizon of 22.4 years, average remaining long-term costs accounted for 42'208 euro or 38'795 euro in the alitretinoin and the standard treatment arm, respectively. Compared with the standard therapy, the addition of alitretinoin yielded an average gain of 0.230 QALYs at the end of the simulation. Accordingly, the incremental cost-effectiveness ratio resulted in 14'816 euro/QALY gained. These results were robust to changes in key model assumptions. CONCLUSION: The therapy for CHE patients is currently insufficient. In our long-term model we identified the treatment with alitretinoin as a cost-effective alternative for the therapy of CHE patients in Switzerland
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